GH does shut down your natural GH
secretion, but it's only for a few hours.. GH
is naturally released throughout the day in a pulsatile fashion. About every four hours you'll have a GH
release from the pituitary, after which point, GH
's negative feedback loop kicks in in response to GH
-1 plasma levels to upregulate somatostatin. This occurs in roughly 4 hour cycles throughout.....life. The amount that is secreted at each pulse varies with age and also state of consciousness. You release much more GH
during sleep than you do during the GH
pulses during the day.
Taking exogenous GH
elevates your plasma GH
levels and incites the GH
negative feedback loop to commence, so it'll throw off your normal pulsatile release, but this will just begin again roughly 4 hours later.
This is why taking GH
doesn't need to be everyday. It's effects are carried out within hours via GH
itself and IGF-1
. The reason we like to use it for a continuous period is that the cummulative results are easier to see.